Splice-on fiber optic connector

ABSTRACT

The present disclosure relates to a splice-on connector configuration having connector body defining a forward fiber buckling region and a rearward splice encapsulation region. The splice encapsulation region can be filled with curable adhesive. The splice encapsulation region can also function to anchor a fiber optic cable.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.16/654,268, filed on Oct. 16, 2019, now U.S. Pat. No. 10,782,476, whichis a continuation of U.S. patent application Ser. No. 16/288,222, filedon Feb. 28, 2019, now U.S. Pat. No. 10,520,676, which is a continuationof U.S. patent application Ser. No. 15/756,450, filed on Feb. 28, 2018,now U.S. Pat. No. 10,281,649, which is a U.S. National Stage Applicationof PCT/US2016/049475, filed on Aug. 30, 2016, which claims the benefitof U.S. Patent Application Ser. No. 62/212,426, filed on Aug. 31, 2015,the disclosures of which are incorporated herein by reference in theirentireties. To the extent appropriate, a claim of priority is made toeach of the above disclosed applications.

TECHNICAL FIELD

The present disclosure relates generally to optical fiber communicationsystems. More particularly, the present disclosure relates to fiberoptic connector and cable assemblies.

BACKGROUND

Fiber optic communication systems are becoming prevalent in part becauseservice providers want to deliver high bandwidth communicationcapabilities (e.g., data and voice) to customers. Fiber opticcommunication systems employ a network of fiber optic cables to transmitlarge volumes of data and voice signals over relatively long distances.Optical fiber connectors are an important part of most fiber opticcommunication systems. Fiber optic connectors allow two optical fibersto be quickly optically connected and disconnected.

A typical fiber optic connector includes a ferrule assembly supported ata front end of a connector housing. The ferrule assembly includes aferrule and a hub mounted to a rear end of the ferrule. A spring is usedto bias the ferrule assembly in a forward direction relative to theconnector housing. The ferrule functions to support an end portion of atleast one optical fiber (in the case of a multi-fiber ferrule, the endsof multiple fibers are supported). The ferrule has a front end face atwhich a polished end of the optical fiber is located. When two fiberoptic connectors are interconnected, the front end faces of theirrespective ferrules abut one another and the ferrules are forcedtogether by the spring loads of their respective springs. With the fiberoptic connectors connected, their respective optical fibers arecoaxially aligned such that the end faces of the optical fibers directlyoppose one another. In this way, an optical signal can be transmittedfrom optical fiber to optical fiber through the aligned end faces of theoptical fibers. For many fiber optic connector styles, alignment betweentwo fiber optic connectors is provided through the use of a fiber opticadapter that receives the connectors, aligns the ferrules andmechanically holds the connectors in a connected orientation relative toone another.

A fiber optic connector is often secured to the end of a correspondingfiber optic cable by anchoring a tensile strength structure (e.g.,strength members such as aramid yarns, fiberglass reinforced rods, etc.)of the cable to the connector housing of the connector. Anchoring istypically accomplished through the use of conventional techniques suchas crimps or adhesive. Anchoring the tensile strength structure of thecable to the connector housing is advantageous because it allows tensileload applied to the cable to be transferred from the strength members ofthe cable directly to the connector housing. In this way, the tensileload is not transferred to the ferrule assembly of the fiber opticconnector. If the tensile load were to be applied to the ferruleassembly, such tensile load could cause the ferrule assembly to bepulled in a proximal direction against the bias of the connector springthereby possibly causing an optical disconnection between the connectorand its corresponding mated connector. Fiber optic connectors of thetype described above can be referred to as pull-proof connectors. Inother connector styles, the tensile strength layer of the fiber opticcable can be anchored to the hub of the ferrule assembly.

Connectors are often installed on fiber optic cables in the factorythrough a direct termination process. In a direct termination process,the connector is installed on the fiber optic cable by securing an endportion of an optical fiber of the fiber optic cable within a ferrule ofthe connector. After the end portion of the optical fiber has beensecured within the ferrule, the end face of the ferrule and the end faceof the optical fiber are polished and otherwise processed to provide anacceptable optical interface at the end of the optical fiber. Splice-onfiber optic connectors are also known. A splice-on fiber optic connectortypically includes a ferrule assembly having a ferrule that supports astub optical fiber. The stub optical fiber includes a rear stub portionthat is spliced to a corresponding optical fiber of a fiber optic cable.Example splice-on fiber optic connectors are disclosed by U.S. Pat. No.9,016,953.

SUMMARY

The present disclosure relates to fiber optic connectors having in-bodysplices such as fusion splices. Certain aspects of the presentdisclosure relate to splice-on fiber optic connectors having robustdesigns that are configured to enhance ease of assembly while also beingcost competitive. Certain aspects of the present disclosure relate tosplice-on connectors having forward portions having provisions foraccommodating fiber buckling and rearward portions having provisions forprotecting splice locations within a curable adhesive. In certainexamples, cables can also be anchored by curable adhesive within therearward portions.

A variety of additional aspects will be set forth in the descriptionthat follows. The aspects relate to individual features and tocombinations of features. It is to be understood that both the foregoinggeneral description and the following detailed description are exemplaryand explanatory only and are not restrictive of the broad inventiveconcepts upon which the embodiments disclosed herein are based.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded view of a fiber optic connector and cable assemblyin accordance with the principles of the present disclosure;

FIG. 2 is a cross-sectional view of the fiber optic connector and cableassembly of FIG. 1;

FIG. 3 is another cross-sectional view of the fiber optic connector andcable assembly of FIG. 1;

FIG. 4 is a side view of a front housing of the fiber optic connectorand cable assembly of FIG. 1;

FIG. 5 is a partially assembled view of the fiber optic connector andcable assembly of FIG. 1;

FIG. 6 is another partially assembled view of the fiber optic connectorand cable assembly of FIG. 1;

FIG. 7 is a diagram showing a splice location for the fiber opticconnector and cable assembly of FIG. 1;

FIG. 8 is a perspective view of a spring stop of the fiber opticconnector and cable assembly of FIG. 1;

FIG. 9 is another perspective view of a spring stop of the fiber opticconnector and cable assembly of FIG. 1;

FIG. 10 is an exploded view of another fiber optic connector and cableassembly in accordance with the principles of the present disclosure;

FIG. 11 is a cross-sectional view of the fiber optic connector and cableassembly of FIG. 10;

FIG. 12 is rear, side perspective view of a front housing of the fiberoptic connector and cable assembly of FIG. 10;

FIG. 13 is a cross-sectional view of the front housing of FIG. 12;

FIG. 14 is a front, side perspective view of a rear housing of the fiberoptic connector and cable assembly of FIG. 10;

FIG. 15 is a perspective view of an adhesive cap that mates with therear housing of FIG. 14; and

FIG. 16 illustrates a splice location for the fiber optic connector andcable assembly of FIG. 10.

DETAILED DESCRIPTION

FIGS. 1-3 illustrate a fiber optic connector and cable assembly 20 inaccordance with the principles of the present disclosure. The fiberoptic connector and cable assembly 20 includes a splice-on fiber opticconnector 22 that is optically coupled to a fiber optic cable 24. Thefiber optic connector 22 includes a dust cap 26, an exterior seal 28(e.g., an O-ring), a front housing 30, a ferrule assembly 32, a spring34, a spring stop 36, an adhesive block 38 (i.e., an adhesive barrier orplug), a rear housing 40, cable supports 42, a rotatable fastener 44(i.e., a rotatable coupler), and a flexible boot 46. The fiber opticcable 24 includes a jacket 48 containing a cable optical fiber 50 andstrength members 52.

Referring to FIG. 2, the front housing 30 and the rear housing 40interconnect to form a connector body 54 of the fiber optic connector22. The front housing 30 includes a front end 56 and a rear end 58. Thefront end 56 of the front housing 30 forms a plug portion of theconnector body 54. The plug portion can be keyed and can be configuredto be received within the port of a corresponding fiber optic adapter ata pre-determined rotational orientation. A fiber optic adapter suitablefor mating with the fiber optic connector 22 is disclosed by U.S. Pat.No. 7,744,288, which is hereby incorporated by reference in itsentirety. The rear housing 40 is mounted over the rear end 58 of thefront housing 30 and extends rearwardly from the rear end 58 of thefront housing 30.

The ferrule assembly 32 of the fiber optic connector 22 mounts withinthe connector body 54. The ferrule assembly 32 includes a ferrule 60having a front end 62 and a rear end 64. The front end 62 of the ferrule60 is often polished and is accessible at the front end 56 of the fronthousing 30. The ferrule 60 defines a central bore 66 that extendsthrough the ferrule 60 along a central longitudinal axis 68 of theferrule 60. The central bore 66 extends along the central longitudinalaxis 68 from the front end 62 to the rear end 64 of the ferrule 60. Theferrule assembly 32 also includes a ferrule flange 70 mounted on theferrule 60. The ferrule flange 70 defines a rearwardly facing surface72. In certain examples, the ferrule flange 70 has a non-circular outershape configured for allowing the ferrule flange 70 to mate with acorresponding receptacle in the front housing 30 in a manner thatprevents the ferrule assembly 32 from rotating about the centrallongitudinal axis 68 relative to the front housing 30. In certainexamples, the ferrule flange 70 can include one or more flats. In oneexample, the ferrule flange 70 has a hexagonal shape that mates with acorresponding hexagonal receptacle defined within the front housing 30.The ferrule assembly 32 further includes a ferrule optical fiber 74secured within the central bore 66 of the ferrule 60. The ferruleoptical fiber 74 includes a rear stub portion 76 that projectsrearwardly from the rear end 64 of the ferrule 60. In certain examples,the ferrule optical fiber 74 is secured within the central bore 66 ofthe ferrule 60 by a curable adhesive such as epoxy. The rear stubportion 76 can also be referred to as a “pigtail” or as a “free endportion.”

The ferrule 60 is preferably constructed of a relatively hard materialcapable of protecting and supporting the ferrule optical fiber 74. Inone example, the ferrule 60 has a ceramic construction. In otherexamples, the ferrule 60 can be made of alternative materials such asUltem, thermal plastic materials such as polyphenylene sulfide (PPS),other engineered plastics or various metals. In one example, the ferrule60 has a length in the range of 5-15 millimeters (mm).

In certain examples, the ferrule assembly 32 is tuned relative to theconnector body 54 such that a core offset of the ferrule optical fiber74 relative to the ferrule 60 is rotationally aligned at a predeterminedrotational orientation relative to the front housing 30. In certainexamples, the ferrule flange 70 has a plurality of flats and the flatmost closely aligned with a core offset of the ferrule optical fiber 74is marked with a core offset marking. In certain examples, the fronthousing 30 defines a viewing opening 80 (see FIG. 1). When the ferruleassembly 32 is loaded into the front housing 30, the ferrule assembly 32is rotationally oriented such that the core offset marking aligns withthe viewing opening 80. In this way, after assembly, it is possible toverify that the fiber optic connector 22 is properly tuned by viewingthe core offset marking through the viewing opening 80. By aligning thecore offset marking with the viewing opening 80, the ferrule assembly 32is rotationally aligned at a desired tuned rotational orientationrelative to a key or other structure provided on the front housing 30.It will be appreciated that a mating relationship between the ferruleflange 70 and the interior of the front housing 30 prevents the ferruleassembly 32 from rotating out of the tuned orientation. Further detailsregarding tuning can be found at U.S. Pat. No. 9,016,953 which is herebyincorporated by reference in its entirety.

When the ferrule assembly 32 is mounted within the connector body 54,the ferrule assembly 32 is axially movable within the connector body 54along the central longitudinal axis 68 between a forward ferruleposition (shown at FIGS. 2 and 3) and a rearward ferrule position. Thespring 34 functions to bias the ferrule assembly 32 toward the forwardferrule position. The spring 34 applies a forward biasing force to therearwardly facing surface 72 of the ferrule flange 70. In the depictedexample, a front end of the spring 34 seats upon the rearwardly facingsurface 72. It will be appreciated that the ferrule flange 70 isrotationally and axially fixed relative to the ferrule 60. Additionally,the ferrule flange 70 is forwardly offset from the rear end 64 of theferrule 60. In the depicted example, the ferrule flange 70 is closer tothe rear end 64 of the ferrule 60 as compared to the front end 62 of theferrule 60.

The adhesive block 38 of the fiber optic connector 22 is mounted withinthe connector body 54 at a position which divides an interior 82 of theconnector body 54 into a forward portion 84 and a rearward portion 86.The adhesive block 38 defines a slot 88 through which the rear stubportion 76 of the ferrule optical fiber 74 extends. In certain examples,the adhesive plug 38 can have a resilient elastomeric construction suchas rubber that allows the slot 88 to flex open so as to receive the rearstub portion 76 of the ferrule optical fiber 74 and then self-close toprevent adhesive from passing though the slot 88.

The cable optical fiber 50 is depicted as being optically spliced (e.g.,fusion spliced) to the rear stub portion 76 of the ferrule optical fiber74 at a splice location 90 within the rearward portion 86 of theinterior 82 of the connector body 54. A curable adhesive 92 fills therearward portion 86 of the interior of the connector body 54. Thecurable adhesive 92 encapsulates the splice location 90 and anchors thefiber optic cable 24 within the rearward portion 86 of the interior ofthe connector body 54. In certain examples, the curable adhesive 92 caninclude a thermo-set adhesive, a thermo-plastic adhesive, a radiationcurable adhesive, or other type of curable adhesive. In certainexamples, curable adhesive includes an epoxy.

The adhesive block 38 is configured to prevent the curable adhesive 92from entering the forward portion 84 of the interior of the connectorbody 54. The forward portion 84 of the interior of the connector body 54forms a fiber buckling region for accommodating buckling of the rearstub portion 76 of the ferrule optical fiber 74 as the ferrule 60 movesfrom the forward ferrule position toward the rearward ferrule position.It will be appreciated that the ferrule 60 is forced to move from theforward ferrule position toward the rearward ferrule position when thefiber optic connector 22 is connected to another fiber optic connectorthrough an intermediate fiber optic adapter.

In certain examples, the fiber buckling region 94 accommodates fiberbuckling corresponding to at least .04 inches of movement of the ferruleassembly 32 from the forward ferrule position to the rearward ferruleposition. In certain examples, the fiber buckling region is configuredto force the rear stub portion 76 of the ferrule optical fiber to bucklealong a single pre-defined fiber buckling plane that aligns with thecentral longitudinal axis 68 of the ferrule 60. In certain examples,buckling occurs along a single macro-bend that extends along the fiberbuckling region.

In certain examples, the curable adhesive chamber defined by therearward portion 86 of the connector body 54 serves both a spliceprotection function and a cable anchoring function. In certain examples,the splice location 90 is imbedded within the curable adhesive 92 withinthe rear portion 86 of the connector body 54. In certain examples, thestrength members 52 of the fiber optic cable 24 can be anchored withinthe curable adhesive that fills the rearward portion 86 of the connectorbody 54. In certain examples, the jacket 48 of the fiber optic cable 24can be bonded to the curable adhesive within the rearward portion 86 ofthe connector body 54. In certain examples, the strength members 52 ofthe fiber optic cable 24 can be relatively stiff so as to have bothtensile and compressive reinforcing characteristics. An example of thistype of strength member includes a fiber reinforced epoxy rod. In otherexamples, the strength members 52 can be configured to provide mostlytensile reinforcement. An example of this type of strength memberincludes Aramid yarn or other type of fibrous strength member. Incertain examples, the fiber optic cable 24 can be a flat-drop cablewhere the jacket 48 has an elongate transverse cross-sectional shape.

In certain examples, the curable adhesive 92 within the rearward portion86 of the connector body 54 also functions to bond the front and rearhousings 30, 40 together. As depicted at FIG. 1, the rear end of thefront housing 30 can include notches, slots or other structures intowhich the curable adhesive can flow to enhance coupling between thefront and rear housings 30, 40. Examples of such structure can includethrough-slots 96 defined laterally through a side wall of the fronthousing 30.

In certain examples, the rear housing 40 can include a sleeve such as acylindrical sleeve 100. In certain examples, the sleeve 100 can be madeof a material that includes metal. One example metal includes stainlesssteel. In certain examples, the sleeve 100 is configured to slide over arear portion of the front housing 30 and is bonded in place at the rearend of the front housing 30 by the curable adhesive 92. A rear end ofthe sleeve 100 can include a circumferential lip 102 over which theflexible boot 46 can snap such that the lip 102 assists in retaining theflexible boot 46 on a rear end 101 of the sleeve 100.

The interior of the sleeve 100 can form the rearward portion 86 of theinterior of the connector body 54. Thus, the interior of the sleeve 100can form the curable adhesive chamber in which the splice location 90 isembedded and in which the fiber optic cable 24 is anchored. The rear end101 of the sleeve 100 is enclosed by two cable supports 42 (see FIGS. 5and 6) that mount within the rear end 101 of the sleeve 100 and can beadhesively bonded to the sleeve 100. The cable supports 104 cooperate todefine a central cable passage 106 having a transverse cross-sectionalshape that matches a transverse cross-sectional profile of the jacket 48of the fiber optic cable 24. As depicted, the transverse cross-sectionalshape of the cable passage 106 is elongated so as to accommodate aflat-style drop cable. The cable supports 104 each define an outerlongitudinal adhesive injection port 108 in fluid communication with therearward portion 86 of the interior of the connector body 54. Duringassembly the various components are assembled together with the splicelocation 90 and the end of the cable 24 within the interior of thesleeve 100 and the cable supports 104 supporting the cable 24 at therear end 101 of the sleeve 100. In this assembled configuration, curableadhesive can be injected into the interior of the sleeve 100 through oneof the adhesive injection ports 108. Injection continues until theinterior of the sleeve 100 is filled with adhesive and adhesive beginsto exit the interior of the sleeve 100 through the other adhesiveinjection port 108. During the adhesive injection process, the adhesiveblock 38 prevents the adhesive from flowing from the rearward portion 86of the connector body 54 into the forward portion 84 of the connectorbody 54.

Referring to FIG. 1, the rotatable fastener 44 is depicted as a threadedcoupling nut but could also be a bayonet-style fastener or other type ofrotatable fastener. In certain examples, the rotatable fastener 44 ismounted over the sleeve 100 and is free to rotate about the centrallongitudinal axis 68 relative to the sleeve 100. As depicted at FIG. 2,the rotatable fastener 44 is captured between the boot 46 and acircumferential shoulder 110 of the front housing 30. When the fiberoptic connector is not in use, the rotatable fastener 44 can be coupledto the dust cap 26 to secure the dust cap 26 over the front housing 30thereby protecting the ferrule 60 and its corresponding ferrule opticalfiber 74. When it is desired to make an optical connection using thefiber optic connector 22, the dust cap 26 can be removed and therotatable fastener 44 can be used to secure the fiber optic connector 22within the port of a corresponding fiber optic adapter. The exteriorseal 28 is mounted within a circumferential groove defined by the fronthousing 30. When the dust cap 26 is mounted over the front housing 30,the exterior seal 28 forms a circumferential seal between the dust cap26 and the front housing 30. Similarly, when the fiber optic connector22 inserted within the port of a corresponding fiber optic adapter, theexterior seal 28 forms a seal between the fiber optic connector 22 andthe fiber optic adapter.

The flexible boot 46 of the fiber optic connector 22 is more flexiblethan the sleeve 100 and is adapted to provide fiber bend radiusprotection at the interface between the fiber optic connector 22 and thefiber optic cable 24. The flexible boot 46 is secured to the rear end101 of the sleeve 100 at a location rearward of the rotatable fastener44. The flexible boot 46 has a tapered outer profile that tapersinwardly as the flexible boot 46 extends in a rearward direction. Incertain examples, the flexible boot 46 can have a segmentedconfiguration to enhance flexibility.

Referring again to FIGS. 1-3, the spring stop 36 (shown at FIGS. 8 and9) of the fiber optic connector 22 mounts within the interior of theconnector body 54. In certain examples, the spring stop 36 is axiallyand rotationally fixed within the interior of the connector body 54. Inone example, the spring stop 36 includes tabs 112 that snap withincorresponding side openings 114 (see FIG. 4) defined by the fronthousing 30 so as to axially and rotationally lock the spring stop 36 inposition relative to the front housing 30. The spring stop 36 includes aforwardly facing surface 116 against which a rear end of the spring 34seats. The spring stop 36 also includes a central front nose section 118that fits inside the rear end of the spring 34. The central front nosesection 118 forms a positive stop that engages the rear end 64 of theferrule 60 to stop rearward movement of the ferrule 60 at the rearwardferrule position. The positive stop has a fixed axial position relativeto the front housing 38 and prevents the ferrule assembly from movingrearwardly to a point where the ferrule flange 70 disengages from itscorresponding mating receptacle defined by the front housing 30. Thepositive stop also limits the range of movement of the ferrule 60 sothat the maximum amount of fiber buckling that occurs in the fiberbuckling region of the fiber optic connector 22 is controlled (i.e., theamount of fiber buckling is directly related to the permitted range ofaxial movement of the ferrule assembly 32.)

Referring to FIG. 2, the spring stop 36 defines a central passage 120through which the rear stub portion 76 of the ferrule optical fiber 74extends. The central passage 120 defines a first cross-dimension CD1 atthe central front nose section 118 and a second cross-dimension CD2 at amain section 122 of the spring stop 36. The main section 122 ispositioned rearwardly with respect to the central front nose section118. The second cross-dimension CD2 is larger than the firstcross-dimension. The spring stop 36 further includes a transitionsection 124 that provides a tapered internal transition between thefirst cross-dimension CD1 at the central front nose section 118 and thesecond cross-dimension CD2 at the main section 122. It will beappreciated that the fiber buckling region corresponding to the forwardportion 84 of the connector body 54 is located within the spring stop36. The adhesive block 38 is mounted at the rear end 58 of the fronthousing 30 and the spring stop 36 includes a rear end positionedadjacent the adhesive block 38. In certain examples, the rear stubportion 76 can buckle along a buckling plane can extend throughelongated side through-slots 126 that are elongated along the centrallongitudinal axis 68 and that are positioned on opposite sides of thecentral longitudinal axis 68. The elongated side through-slots 126 arepositioned at the major section 122 of the spring stop 36 and areconfigured to allow the rear stub portion 76 of the ferrule opticalfiber 74 to flex through one of the elongated side through-slots 126during buckling of the rear stub portion 76 of the ferrule optical fiber74. Thus, a larger degree of buckling is accommodated.

To assemble the fiber optic connector and cable assembly 20, the ferruleassembly 32 can be loaded into the front housing 30 through the rear end58 of the front housing 30. Preferably, the ferrule assembly 32 isloaded at a tuned orientation in which the tuning marking on the ferruleflange 70 aligns with the viewing opening 80 of the front housing 30.Once the ferrule assembly 32 has been loaded into the front housing 30,the spring 34 is inserted over the rear stub portion 76 of the ferruleoptical fiber 74 and loaded into the front housing 30 through the rearend 58 of the front housing 30. Next, the spring stop 36 is insertedover the rear stub portion 76 of the ferrule optical fiber 74 and loadedinto the front housing 30 through the rear end 58 of the front housing30. Preferably, the spring stop 36 is snapped in position relative tothe front housing 30 such that the spring 34 is captured between theferrule flange 70 and the forwardly facing surface 116 of the springstop 36. As part of the initial assembly process, the rotatable fastener44 and the to rear sleeve 100 can be inserted over the fiber optic cable24 as shown at FIG. 7. Thereafter, the jacket 48 can be stripped awayfrom the end of the fiber optic cable 24 to expose the strength members52 and the cable optical fiber 50. The cable optical fiber 50 as well asthe rear stub portion 76 of the ferrule optical fiber 74 can then bestripped, cleaved and cleaned. Next, the rear stub portion 76 of theferrule optical fiber 74 can be spliced to the cable optical fiber 50 atthe splice location 90. Thereafter, the rear sleeve 100 is slid over therear end 58 of the front housing 30 and the cable supports 104 areloaded into the rear end 101 of the sleeve 100 with the cable 24supported within the central cable passage 106 defined by the cablesupports 104. FIG. 6 shows the cable supports 104 supporting the cable24 at the rear end of the sleeve 100. Next, curable adhesive is injectedthrough one of the adhesive injection ports 108 to fill the interior ofthe sleeve 100 with curable adhesive thereby encapsulating the splicelocation 90 as well as the strength members 52 of the cable 24 and theend portion of the jacket 48 of the cable 24. Once the curable adhesivehas been cured, the rotatable fastener 44 is slid over the sleeve 100and the boot 46 is snapped over the rear end of the sleeve 100 tocomplete the assembly process.

FIGS. 10-16 show another fiber optic connector and cable assembly 220 inaccordance with the principles of the present disclosure. The fiberoptic connector and cable assembly includes a splice-on fiber opticconnector 222 optically coupled to a fiber optic cable 224. Thesplice-on fiber optic connector 222 is depicted as an SC-style fiberoptic connector. Also, the fiber optic cable 224 is depicted as a roundcable. The fiber optic connector 222 includes a connector body 254formed by a front housing 230 coupled to a rear housing 240. The ferruleassembly 32 and the spring 34 mount within the front housing 230. Therear housing 240 functions as a spring-stop for retaining the ferruleassembly 32 and the spring 34 within the front housing 230. The fiberoptic connector 222 further includes an adhesive block 238 and anadhesive cap 241 that mount within the rear housing 240. The fiber opticconnector 222 further includes a flexible boot 246 that mounts on a rearend of the rear housing 240 and a release sleeve 223 that mounts overthe front housing 230. The fiber optic cable 224 has a jacket 248 havinga round transverse cross-sectional shape. The fiber optic cable 224further includes a cable optical fiber 250 and can include strengthmembers 252 such as Aramid yarn or other fibrous strength members.

The connector body 254 of the fiber optic connector 222 includes thefront housing 230 coupled to the rear housing 240. The front housing 230includes a front end 256 and a rear end 258. The front end 256 forms aplug portion of the connector body 254 having an SC style form factor.The front housing 230 can include shoulders 259 that are engaged bycorresponding latches when the fiber optic connector 222 is insertedwithin a corresponding fiber optic adapter. The release sleeve 223 isaxially movable relative to the front housing 230 and is adapted fordisengaging the latches of the fiber optic adapter from the shoulders259 when it is desired to remove the fiber optic connector 222 from thefiber optic adapter. For example, the release sleeve 223 can includeramps 225 that force the latches away from the shoulders 259 when therelease sleeve 223 is retracted so as to allow the fiber optic connector222 to be removed from the fiber optic adapter.

The ferrule assembly 32 mounts within the front housing 230 such thatthe front end 62 of the ferrule 60 is accessible at the front end 256 ofthe front housing 230. Similar to the previously described example, theferrule assembly 32 is movable within the connector body 254 along thecentral axis 68 between a forward ferrule position and a rearwardferrule position. The spring 34 biases the ferrule assembly 32 towardthe forward ferrule position.

The adhesive block 238 of the fiber optic connector 222 divides theinterior of the connector body into a forward portion 284 and a rearwardportion 286. In the depicted example, the forward and rearward portions284, 286 are defined within the rear housing 240. The adhesive block 238defines a slot 288 through which the rear stub portion 76 of the ferruleoptical fiber 74 extends. The adhesive block 238 can have a resilientconstruction that allows the slot 288 to be flexed open to accommodatereceipt of the rear stub portion 76 of the ferrule optical fiber 74. Thecable optical fiber 250 is spliced (e.g., fusion spliced) to the rearstub portion 76 of the ferrule optical fiber 74 at a splice location 290within the rearward portion 286 of the interior of the connector body254. A curable adhesive is used to fill the rearward portion 286 of theinterior of the connector body 254. The curable adhesive encapsulatesthe splice location 290 and anchors the cable 224 within the rearwardportion 286 of the interior region of the connector body 254. Theadhesive block 238 is configured to prevent the curable adhesive fromflowing into the forward portion 284 of the interior of the connectorbody 254. The forward portion 284 of the interior of the connector body254 forms a buckling region for accommodating buckling of the rear stubportion 76 of the ferrule optical fiber 74 as the ferrule 60 moves fromthe forward ferrule position toward the rearward ferrule position.

Referring to FIG. 10, the rear housing 240 can be secured to the fronthousing 230 by a snap-fit connection. For example, the rear housing 240can fit inside the front housing 230 and can include tabs 247 that snapwithin corresponding openings 249 of the front housing 230 (see FIGS. 12and 13).

The boot 246 is preferably more flexible than the rear housing 240 andmounts at a rear end of the rear housing 240. Similar to the previouslydescribed boot 46, the boot 246 functions to provide bend radiusprotection at the cable-to-connector interface. The flexible boot 246can have a tapered, segmented configuration to enhance flexibility.

In certain examples, the rear housing 240 can function to define boththe forward portion 84 (i.e., the fiber buckling region) of theconnector body 54 and the rearward portion 86 (i.e., the spliceencapsulating and cable anchoring region) of the connector body 54. Theforward and rearward portions 284, 286 are defined within an open sidedslot 261 that extends through the entire length of the rear housing 240.The adhesive block 238 mounts within the open sided slot 261 to providean adhesive barrier between the forward and rearward portions 284, 286.The rearward portion 286 is laterally enclosed by the adhesive cap 241(see FIG. 15) that is secured to the rear housing 240 so as to cover theportion of the open sided slot 261 corresponding to the rearward portion286. In certain examples, the adhesive cap 241 is pressed within theopen sided slot 261. In certain examples, the adhesive cap 263 issecured to the rear housing 240 by a snap-fit connection.

In the depicted example, the rear housing 240 includes a central frontnose section 218 that fits within the rear end of the spring 34 andfunctions as a positive stop that engages the rear end 64 of the ferrule60 to stop rearward movement of the ferrule at the rearward ferruleposition. The rear housing 240 also includes a forwardly facing surface216 against which a rear end of the spring seats. In certain examples,the central front nose section 218 extends for at least one quarter ofthe length of the spring 34 when the ferrule assembly 32 is in theforward ferrule position.

The open-sided slot 261 defines a fiber passage in which the rear stubportion 76 of the ferrule optical fiber 74 is received. The fiberpassage of the rear housing 240 defines the front and rear portions 284,286 of the interior of the connector body 254. The adhesive block 238mounts within the rear housing 240. The open side of the open-sided slot261 is enclosed by the adhesive cap 241 at the rearward portion of theinterior of the connector body 254. The adhesive cap 263 defines anadhesive injection port 265. The open-sided slot 261 has a transversecross-sectional shape that is elongated in a lateral orientation toaccommodate fiber buckling generally along a single plane that alignswith the central longitudinal axis 68 of the ferrule 60. In certainexamples, the transverse cross-sectional shape can have a length L thatextends in a lateral orientation and a width W perpendicular to thelength. In certain examples, the length L can be at least two times aslarge as the width W. It will be appreciated that the elongatedcross-sectional shape is preferably provided along the forward portion284 of the connector body 254 to encourage fiber buckling along thelonger orientation.

In certain examples, the fiber optic connector and cable assembly 320 isassembled by first sliding the boot 246 over the fiber optic cable 224.Next, the jacket 248 of the cable 224 is stripped from the end of thecable 224 to expose strength members and the cable optical fiber 250.The cable optical fiber 250 is then stripped, cleaved and cleaned.Similarly, the rear stub portion 76 of the ferrule optical fiber 74 isstripped, cleaved and cleaned. The spring 34 is then inserted over therear stub portion 76 and the rear stub portion 76 is spliced to thecable optical fiber 250. Thereafter, the ferrule assembly 32 is loadedinto the front housing 230 through the rear end of the front housing230. Next, the adhesive block 238 is loaded into the open-sided slot 261of the rear housing 240. Thereafter, the fiber structure formed by therear stub portion 76 spliced to the cable optical fiber 250 is insertedinto the open-sided slot 261 and into the slot 288 defined by theadhesive block 238. The adhesive cap 241 is then snapped into theopen-sided slot 261 to enclose the adhesive chamber defined by the rearhousing 240. Next, the rear housing 240 is snapped into the fronthousing 230 such that the ferrule assembly 32 and the spring 34 arecaptured therein. Curable adhesive is then injected into the adhesivechamber through the adhesive injection port 265 defined by the adhesivecap 241. In this way, the splice location 290 as well as the end of thefiber optic cable 224 are encapsulated by adhesive within the adhesivechamber defined by the rear housing 240. The boot 246 is then insertedover the rear of the rear housing 240.

While various specific dimensions are provided above, it will beappreciated that the dimensions are applicable to some embodiments andthat other embodiments within the scope of the present disclosure mayuse dimensions other than those specifically provided. Similarly, whilevarious manufacturing tolerances are provided above, it will beappreciated that the manufacturing tolerances are applicable to someembodiments and that other embodiments within the scope of the presentdisclosure may use manufacturing tolerances other than thosespecifically provided. The above specification, examples and dataprovide a description of the inventive aspects of the disclosure. Manyembodiments of the disclosure can be made without departing from thespirit and scope of the inventive aspects of the disclosure.

What is claimed is:
 1. A method of assembling a fiber optic connectorand cable assembly extending axially from a front end to a rear end,comprising steps of: a) loading a ferrule assembly into a front housingthrough a rear end of the front housing, the ferrule assembly includinga ferrule optical fiber terminated at a ferrule; b) inserting a springover a rear stub portion of the ferrule optical fiber; c) placing aspring stop over at least a portion of the rear stub portion and loadingat least a front portion of the spring stop into the front housingthrough the rear end of the front housing; and d) subsequent to c),splicing the rear stub portion to a cable optical fiber at a splicelocation rearward of the spring stop.
 2. The method of claim 1, whereinthe splicing is fusion splicing.
 3. The method of claim 1, wherein thestep c) causes the spring to be captured between a flange of the ferruleand a forwardly facing surface of the spring stop.
 4. The method ofclaim 1, wherein the spring stop includes a forward nose portion, andwherein the step c) includes sleeving the spring over the forward noseportion.
 5. The method of claim 1, further comprising sliding a rearhousing into the rear end of the front housing such that the splicelocation is positioned within the rear housing.
 6. The method of claim5, further comprising injecting adhesive into the rear housing via anadhesive injection port.
 7. The method of claim 6, further comprisingcuring the adhesive.
 8. The method of claim 1, wherein the spring stopincludes an axially elongated through slot into which a portion of theferrule optical fiber can buckle.
 9. The method of claim 8, furthercomprising causing a portion of the optical fiber to buckle into thethrough slot.
 10. The method of claim 5, wherein the rear housingincludes tabs and the front housing includes openings; and wherein thesliding a rear housing includes snapping the tabs into the openings. 11.The method of claim 1, further comprising, prior to (d), sliding a bootover a cable having the cable optical fiber.
 12. The method of claim 11,further comprising, prior to (d), stripping a jacket from an end of thecable to expose the cable optical fiber.
 13. The method of claim 12,further comprising cleaving and cleaning the cable optical fiber.
 14. Amethod of assembling a fiber optic connector and cable assemblyextending axially from a front end to a rear end, comprising steps of:a) sliding a boot over a fiber optic cable; b) subsequent to a)stripping a jacket of the fiber optic cable at a front end of the fiberoptic cable to expose strength members and a cable optical fiber; c)subsequent to b), stripping, cleaving and cleaning the cable opticalfiber; d) stripping, cleaving and cleaning a rear stub portion of aferrule optical fiber; e) subsequent to c) and d), inserting a springover the rear stub portion; f) subsequent to e), splicing the rear stubportion to the cable optical fiber; g) subsequent to f), loading aferrule assembly including a ferrule and the spliced ferrule opticalfiber into a front housing through a rear end of the front housing; h)inserting a fiber structure formed by the rear stub portion spliced tothe cable optical fiber into a rear housing; and i) subsequent to h),snapping the rear housing into the front housing such that the ferruleassembly and the spring are captured therein.
 15. The method of claim14, wherein h) is performed after g).
 16. The method of claim 14,further comprising, subsequent to i), injecting curable adhesive intothe rear housing to encapsulate the splice location by the curableadhesive.
 17. The method of claim 14, further comprising, subsequent toi), inserting the boot over a rear of the rear housing.
 18. The methodof claim 16, further comprising, subsequent to the injecting, insertingthe boot over a rear of the rear housing.
 19. A method of assembling afiber optic connector and cable assembly extending axially from a frontend to a rear end, comprising steps of: a) stripping a jacket of a fiberoptic cable at a front end of the fiber optic cable to expose strengthmembers and a cable optical fiber; b) subsequent to a), stripping,cleaving and cleaning the cable optical fiber; c) stripping, cleavingand cleaning a rear stub portion of a ferrule optical fiber; d)subsequent to b) and c), inserting a spring over the rear stub portion;e) subsequent to d), splicing the rear stub portion to the cable opticalfiber; f) subsequent to e), loading a ferrule assembly including aferrule and the spliced ferrule optical fiber into a front housingthrough a rear end of the front housing; g) subsequent to f), insertinga fiber structure formed by the rear stub portion spliced to the cableoptical fiber into a rear housing; and h) subsequent to g), snapping therear housing into the front housing such that the ferrule assembly andthe spring are captured therein.